Field of the Invention
The present invention relates to a muffler assembly equipped with an active control valve for a vehicle, and more particularly, to a muffler assembly including two main mufflers separate from each other, and an active control valve centrally disposed between the main mufflers, thereby being capable of achieving an effect exhibited when two active control valves are used, using one active control valve.
Description of Related Art
Generally, exhaust gas burning in an engine of a vehicle has a significantly high temperature. Furthermore, velocity of exhaust gas is almost equal to sonic velocity. When such exhaust gas is directly exhausted into the atmosphere, exhaust gas generates an intense explosion sound while expanding abruptly. To this end, a separate muffler is installed in an exhaust gas path in the vehicle to lower the temperature and pressure of exhaust gas, thereby reducing exhaust noise.
FIG. 1 is a view illustrating a conventional muffler installed in a vehicle, and FIG. 2 is a view illustrating an active control valve additionally installed in the conventional muffler.
As illustrated in FIG. 1, an exhaust pipe 1 is connected to an exhaust manifold of an engine to guide flow of exhaust gas. Coupled to the exhaust pipe 1 are a catalytic converter 2 for converting harmful substances contained in exhaust gas into harmless substances and a muffler 3 for decreasing exhaust noise.
In this case, as illustrated in FIG. 2, tailpipes 4 discharge exhaust gas passing though the muffler 3 to an outside. Additionally, an active control valve 5 is mounted in one of the tailpipes 4 to change an exhaust path of exhaust gas in accordance with driving conditions of the vehicle.
In detail, during a constant or low engine speed period, the active control valve 5 is closed, such that exhaust gas is exhausted through only one tailpipe 4, in which the active control valve 5 is not mounted. On the other hand, during an accelerating or high engine speed period, the active control valve 5 is opened, such that exhaust gas is exhausted through both of the tailpipes 4.
The illustrated case shows an example in which two tailpipes 4 are coupled to the muffler 3 and one active control valve 5 is used. However, when four tailpipes are coupled to the muffler, two active control valves may be used. As the number of the active control valves is increased, there is an advantage in that variation of exhaust pressure and exhaust tone of exhaust gas may be maximized.
The active control valve 5 is used as a muffler tuning element for high performance vehicles capable of differentiating exhaust pressure and exhaust tone of exhaust gas. However, this tuning element is considerably expensive and, as such, there may be a limitation in increasing the number of active control valves 5.
Furthermore, as illustrated in FIG. 2, a branch chamber 3a of the muffler 3 functions only to bilaterally transfer exhaust gas. In this case, the branch chamber 3a is not a volume for expansion, resonance, and sound absorption used for tuning of the muffler 3 and, as such, the branch chamber 3a may be a dead space due to low space utilization.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.